Conservative vs. operative treatment for humeral shaft fractures: a meta-analysis and systematic review of randomized clinical trials and observational studies

This meta-analysis aimed to compare conservative vs. operative treatment for humeral shaft fractures in terms of the nonunion rate, reintervention rate, permanent radial nerve palsy rate, and functional outcomes. Secondarily, effect estimates from observational studies were compared with estimates of randomized clinical trials (RCTs). The PubMed/Medline, Embase, CENTRAL (Cochrane Central Register of Controlled Trials), and CINAHL (Cumulative Index to Nursing and Allied Health Literature) databases were searched for both RCTs and observational studies comparing conservative with operative treatment for humeral shaft fractures. A total of 2 RCTs (150 patients) and 10 observational studies (1262 patients) were included. The pooled nonunion rate of all studies was higher in patients treated conservatively (15.3%) vs. operatively (6.4%) (risk difference, 8%; odds ratio [OR], 2.9; 95% confidence interval [CI], 1.8-4.5; I2 = 0%). The reintervention rate was also higher for conservative treatment (14.3%) than for operative treatment (8.9%) (risk difference, 6%; OR, 1.9; 95% CI, 1.1-3.5; I2 = 30%). The higher reintervention rate was predominantly attributable to the higher nonunion rate in patients treated conservatively. The permanent radial nerve palsy rate was equal in both groups (OR, 0.6; 95% CI, 0.2-1.9; I2 = 18%). There appeared to be no difference in mean time to union and mean Disabilities of the Arm, Shoulder and Hand scores between the treatment groups. No difference was found between effect estimates form observational studies and RCTs. This systematic review shows that satisfactory results can be achieved with both conservative and operative management; however, operative treatment reduces the risk of nonunion compared with conservative treatment, with comparable reintervention rates (for indications other than nonunion). Furthermore, operative treatment results in a similar permanent radial nerve palsy rate, despite its inherent additional surgery-related risks. No difference in mean time-to-union and short-term functional results was detected.